There has, but it's mainly targeted towards workarounds for the walled gardens.

For $100 on AliExpress you'll find ink by the liter instead of milliliter, syringes or custom cartridges to refill the printer, and "chip reset" tools, if applicable.

It sucks that you need to do that, but with a bit of research in advance you can get a cheap printer and escape the razorblade model.

I have a printer I like but my experience is that the minute I print something the ink cartridge announces it’s low. It’ll run for a long time, but it’s like having a neighbor who’s fire alarm is going off at all times. It sours the ownership experience, even if I buy and keep a bucketful of spare ink cartridges handy.

There has been innovation. Epson marketed new inkjets that take liquid ink which is quite cheap. Something like $10 per bottle which can last for thousands of pages. Perhaps you should check them out. The line-up is called "ink tank". Other manufacturers have followed suit with similar products.

Third party companies were producing retrofit continuous ink systems years before the printer manufacturers introduced introduced ink tank printers.

With ink tank printers, you pay extra to escape the "razor and blades" pricing model. Probably worth it if you print sufficient volume using an inkjet.

I don't know if you checked it out, but there are a lot of specific book printing services like Kindle Direct Publishing where they will print your book for a lot less than that. The quoted base price for a large trim premium (larger than 6.12inx9in) color print book is $1 + $0.08 per page.

Why should printing be cheaper in 2023 than 1997?

you've been spoiled by moore's law, most physical goods can't become 1000x cheaper and better, especially not in a dying market like home printing